Dlink routers won't allow net access

For some reason my DLink router quit allowing me to have internet access. When I connect my Cisco 675 DSL modem directly to my PC, using an integrated Marvell Yukon 88E8001 PCI connector, I have no problems. As soon as I try to put into the loop either a D-Link 614+ 802.11b or a DLink 524 802.11g wireless router, there no internet connection. I've done everything suggested by my DSL provider and DLink. Swapped cables, enabled / disabled Zone Alarm, and reset both the router and modem. The only thing I have't done is sacrifice a virgin. I noticed my connection was going to pot around Monday or Tuesday when I was trying to configure another PC using a wireless connection. I usually got a very good signal strength, but it was showing only a fair to poor strength. My laptop used to connect with no problems and then it quit being able to connect.
Any suggestions?

I did a reset using the pinhole reset button. Nada.

I went thru the entire install again, swapping out the old cables, including the one that came with the 524 and used one my ISP provided with the modem. I ran the setup wizard from the install disc after going through all of the set up through the URL based wizard.

Wireless is 5x5 and treetop tall. Internet access is dead. The only thing I can figue is the 524 has a bad connection internally as my 802.11b DI-614+ works just fine now.

"Curiouser and curiouser", said Alice.

PS - I wrote this message on my laptop with an integral Broadcom 802.11g